title: Otolith organ function according to subtype of benign paroxysmal positional vertigo.
abstract: OBJECTIVE
  The clinical features and treatment outcomes of benign paroxysmal positional vertigo (BPPV) are known to be different depending on the type of and involved canal. This difference could be due to differences in the functional change of the otolith organ.
  
  
  METHODS
  Case series.
  
  
  METHODS
  Forty-nine patients were diagnosed to primary BPPV; 18 were categorized as posterior canal canalolithiasis (PC canalolithiasis), and 31 were categorized as horizontal canal (HC) BPPV with canalolithiasis or cupulolithiasis (HC canalolithiasis or HC cupulolithiasis). Diagnostic interventions to measure vestibular functions were performed such as electronystagmography (ENG), videonystagmography (VNG), and static and dynamic subjective visual vertical (SVV). BPPV was confirmed with nystagmus during positioning/positional test under ENG and VNG. Static SVV was recorded with a light-emitting diode (LED) bar located in front of the patients before eccentric rotation and dynamic SVV was recorded during eccentric rotation with the LED bar. SVV angles were read by the examiner and analyzed. The measured values were compared to those of normal controls and each other.
  
  
  RESULTS
  Dynamic SVV toward the lesion side in all subtypes of BPPV were significantly different from those of the controls; HC cupulolithiasis showed significantly lower values than those of PC canalolithiasis and HC canalolithiasis.
  
  
  CONCLUSIONS
  HC cupulolithiasis shows a lesser degree of utricular dysfunction compared with other subtypes. It could postulate the difference of pathophysiology between canalolithiasis and cupulolithiasis.
  
  
  METHODS
  4.
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, Kyung Hee University Hospital at Gangdong, Seoul, Korea.
authors.forename: Sun K
authors.initials: SK
authors.lastname: Lee
authors.forename: Su J
authors.initials: SJ
authors.lastname: Kim
authors.forename: Moon S
authors.initials: MS
authors.lastname: Park
authors.forename: Jae Y
authors.initials: JY
authors.lastname: Byun
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D065635:Benign Paroxysmal Positional Vertigo; D004584:Electronystagmography; D005133:Eye Movements / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D019416:Head Movements / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010037:Otolithic Membrane / Q000503:physiopathology*; D011187:Posture / Q000502:physiology*; D012189:Retrospective Studies; D012665:Semicircular Canals / Q000503:physiopathology; D014717:Vertigo / Q000175:diagnosis / Q000503:physiopathology*; D055815:Young Adult
keywords: Benign paroxysmal positional vertigo; otolith organ; subjective visual vertical